Micrometer gauge



Patented Oct. 2 5, 1927.

UNITED sTATE- s PATENTQFFICE.

ROBERT GBIFI'IN DE LA MATER, or woaons'rnn, MAssAoHu-snrrs, .Assmrnoa- 'ro` REED SMALL TOOL iWORKS, OF WORCESTEB,. MIASA'CHUSETTS, A CORPORATION OF IASSCHUSETTS.

Application filed April 6,

sity for :such series being due to the fact that it has been impracticable to provide for extensive longitudinal moveinent of the micrometer screw in an attempt to increase the range of a given instrument Without impairing .the accuracy of precision of measurement. i

I An object ofthis invention is to provide an improved :simple and reliable means may be extended without necessitating undue longitudinal movement of the microm-- eter screw and Without .otherwise detracting from the required delicacy and Precision in measuring Operations. I

Other objects and advantages of the linvention will become apparent from' the following description when taken in connection' with the accompanying drawings in which- Figure 1 is a side elevationof a micrometer gauge with which-the attachments embodying this invention are adapted to be used, the extension anvil holder beingshown in section and supporting` one of a 'proposed series' of extensionv anvils; Figur-es 2 and 3 are views showing in elevation additional extension anvils of different lengths, which anvils a are interchangeable with each other and 40. with the extension anvil shown in Figure 1;

and Figure 4 isa view in elevation of the extension anvil holder shown in Figure 1.

Referring to the drawings, the numeral 5 indicates a curved two-armed frame of a micrometer ,eauge` one arm' 'being provided with an anvil 7 and the other arm8 having mounted thereon a m'icrometer mechanism 10 of any suitable ty e. post or screw 11, of t e micrometer mechanism 10, is adapted for only relatively short longitudinal movement toward and away from the anvil 7 the extent of such movement being, for example`l one inch for a gauge having a normal maximum limit of whereby the range lof a given instrument.

The micrometer MICROMET ER. GAVT'GE.

1927. serial No. 181,880.

four inches, as herein: illustrated. Thatjis to say, without the attachment herein shown and hereinafte'r more particularly described, f

the maximum distance afforded between the anvil 7 and the outer, end of the microineter screw. 11 would VJoe 4 inches and the minimum d'istance aifordedbetween the anvil 7 and the outer end. of the screw 11 would be three inches, assuming that the screw 11 is adapted formaximum' movement of one inch either: toward or away from the anvil 7. Itwill therefore beappreciated that any measurement with the .so-called. four inch 'gauge herein shown, Would, in the absence of the i 'attachments hereinafter more particularly described, ;be limited to dimensions ranging from three to fourinches. i w

According to this invention the .range of measurement is amplified so thaty in the ex.-

ample given the ,qau-,qe'mav be used in measuring dimensionsranging from zero to four inches.. without increaslng' the. extent of longitu'dinal movement of the-micrometer, screw. If, foifiexample, x it is desired toV measure an object orv article ranging-V in thickness from zero to one inch, an extension.

anvil 12,'.shown in lFigure V1, is clamped in' position on the4 gaue'e; This anvil is in the. form of a round rod having adiam-eter-substantially equal to the diameter vof thekscrew 11'and provided at. one' endwith-a headl 13.L

This anvil 12 ,is secnred to the'arm in axialf alignment with the. screw 11, and the means for effectinz such attachment of the anvil 12 to the arm 6 is in the form of an extensionanvil holder 14. This extension anvil holder comprises an anvil-embracing part consistlng of a tubular sleeve 15 which is adapted to receive the extension anvil 12 and which is counter-bored in order to provide. a shoulder 16 adapted to engage thehe'ad 18 of the' extension anvil. p The sleeve 15 is cut away intermediate its ends. as shown 'at 17, in order ceived within the sleeve 15, as shown in Figure The anvil holder 14 is clamped in position on ythe arm 6 by a thumb screw 18,

` that the outer -end of the arm 6 may be recarriedV by the anvil holder and having threaded 'engagement with the internally) screw-threaded end of the sleeve 15, as shown most clearly in `Figure 1. `eBy-I'unning the screw 18 down into firm engagement with the arm 6. the shoulder 16 of the sleeve 15' is forced into intimate engagement w with the head 13 of the extension anvil 12, whereby such anvil is vheld in position with its head 13 firmly seated against the flat sur-' face of the anvil 7. In order to insure the extension-anvil holder 14 against `accidental displacement, the screw18 m'ay be rovided with a pointedend 19 which is a apted to enter a corresponding recess in the adjacent' face or portion of the arm 6, as indicated in Figurel. t

As thus far described the micrometer `gaiige shown is adapted, with a movement of the microineter screw of one inch,`to measure dimensions rangingifroin threeto four inches and from zero to one inch. By simple substitution of two other extension anvils it may i bridge the distance between these extrenies.

' introduced into the holder through such screw-threadedend; 'The screw 18) is then screwed into engageinent with the arni 6,`and f thereby the head of the extension anvil, '13* Tith the extension anvil 12', shown inFigure 2; it .may measure dimensions from two`` tofthree inches and with the 'extensionanvi'l 12"; shown in Figure 3, 1t mayl` measure diinensions froin one to two inclies. To

make this siibstitution theholder is removed from' the head 6, which may be done after slightly unscrewing the thiimb screwv 178, and

thexthunib screw is thenconipletely with-' drawn fronithe screw-t-hreaded end of the sleeve landthe extensionjanvill is then withdrawn from the sleeve through such screw-threaded end of'the sleeve. Which. .everone ofthe two shorter extension anvils 12'i`or 12 it is desired to iise'noay'then be of the anvil 12''` ori`13'f of the anvil ``13' is forced. into` intirnate' engagement with the` anvil-7 as previoiisly described in connection with the head 18 of the extension anvil 12.'

'While extension `anvils ofv` only three ``different `lengths are hereinfshown and w described, it will be understoodthat as 'many to said franieysaid sleeve having a shoiilder forined thereon, an extension anvil having a head forined tliereon,` said extension `anvilV being adapted to be introduced Viiito said sleeveivith said head engaging said shoiilder, and means for clainping said framev to said holder and claniping said headintermediatel said fraine and saidshoiilder whereby said extension aiivil is seciired against moveinent with respect to said franie and saidholder.

` 2. For usein connection witlioa microinetert caliper `Qauge having Ueshaped frame pro vid'ed at one end with an anvil land 'at the other end with ainiCrOineterinehaniSm, an attachjii'ient coniiirising an extension an`vil having a head forined thereonat one end,1 and anriextension anvil holder including` 570 a ciut-away portion, saidopening being at one end threaded and at the other end``7 sleevehaving an opening tlierethroiigh,"and

adapte'd to'receive1 said extensionanvil and being providedlwith a shoulderwithfwhiclf` w the head on said extension anvil enlgiages,`` and a screw' in the threaded end. of said sleeve adapted to engage that endof the U-shaped fraine carrying the* anvil for cl'ainpingisaid sleeve to'theend of said fraine:

with the end of tlielheadofsaid extension anvil in eng'agement with the anvil iii said frame.```I i 7 3 In testimony whereof,`` I 'have aflixedniv signature to fthis specification.

ROBERT ciiirrmns LA mniam a the scope `of'the subjoined claiins;` ,3. i 

